Ok, my 2 cents here. I'm a hobby photographer and love of trains makes it even more exciting.
That being said, anyone has rights to any area for photography if they are off private land. Private land. If you have permission then yes, have at it, but it seems like theres no way anyone can control this issue if it's on public land. It does suck when you wait (paid or not) to get the perfect shot and then have it ruined. Yes, Photoshop is good for wires & little things but not all have it or can do it well.
I often do these kinds of shoots but that being said I'm on a limited budget and if I can get a great shot by not paying and by not getting in others way that did pay I'll continue to do it. I would expect the same for those that did pay and be polite to those who did not.
The reason being is that some do this for fun like I do, many just like to photograph trains or anything else because it gives them pleasure. People who don't pay may be older people or disabled or just don't have the money to pay for something that is basically on public land and can be done without worrying about what you can do without to afford to pay to get a good photo.
Being one of those people on a very limited budget because of health concerns, I'm sort of put off by the comments that pretty much make those without the funds to have fun and pay for it look like leeches bagging off of others. Sorry but it should have been in private or in a less accusing way. We are not all that lucky to have money to do things we enjoy.